#ifdef __cplusplus
#include <cstring>
#include <cstdio>
#include <cerrno>
#else
#include <string.h>
#include <stdio.h>
#include <errno.h>
#endif

int main () {
  FILE * pFile;
  pFile = fopen ("unexist.ent","r");
  if (pFile == NULL)
    printf ("Error opening file unexist.ent: %s\n", strerror(errno));
  return 0;
}